The present invention relates to power tools and, more particularly, to a liner to protect tools or bits from marring or nicking while in a tool holder of a power tool.
In power tools, specifically hobby tools, routers and rotating power tools, it is desirable to utilize various types of tools and/or bits. Ordinarily, these tools have some type of working head and an elongated shaft to be maintained in the power tool. Depending upon the tool head holder, the tool shafts are sized to be received in the holders. In the event that the tool shaft has a diameter, different than what is normally received by the tool holder, another tool holder is substituted on the power tool so that the tool may be retained in the power tool.
The tool holders utilize locking elements, such as balls, which are biased in the tool holder to maintain the tool in the holder. The elements apply a holding force onto the tool shafts to maintain the tools within the tool holder. In the event the biased elements are balls or the like, the balls may have a tendency to mar or nick the shaft of the tool. Thus, it is desirable to protect the tool shafts from marring, nicking or the like by the tool holders.
Accordingly, it is an object of the present invention to provide a liner which protects tools shafts from marring, nicking or the like. The liner of the present invention may also increases the friction holding force of the tool within the liner.
Accordingly, in accordance with a first aspect of the present invention, a liner for a tool holder comprises a hollow member with a wall defining an interior periphery and an exterior periphery. The interior periphery is sized to receive a tool and the exterior periphery is sized to fit within a tool holder. The hollow member includes two arcuate portions which define an elongated overall cylindrical configuration. Each arcuate portion includes at least one axial slot. The slots enable a reduced force to insert the tool into the hollow member. The exterior periphery of each arcuate member includes one or more axial grooves. A plurality of members project from the interior periphery of the hollow member to contact the tool. This provides increased frictional holding of the tool within the hollow member. The projection members surround the interior periphery to provide a corrugated pattern. One of the arcuate portions is thicker than the other. Both arcuate portions have the same thickness at their grooves so that the cam sleeve roll out tracks with the tool bit roll out. One arcuate portion defines an arc of about 200.degree. and the other arcuate portion defines an arc of about 150.degree..
In accordance with a second embodiment of the present invention, a power tool comprises a housing with a motor within the housing. A power source is coupled with the motor. An output member is likewise coupled with the motor. An actuation member is coupled with the power source and the motor to power the motor which, in turn, rotates the output member. A tool holder is coupled with the output member. A tool, which includes a shank, is coupled with the tool holder. A liner is in the tool holder. The liner comprises a hollow member with a wall defining an interior periphery and an exterior periphery. The interior periphery is sized to receive a tool and the exterior periphery is sized to fit within a tool holder. The hollow member includes two arcuate portions which define an elongated overall cylindrical configuration. Each arcuate portion includes at least one axial slot. The slots enable a reduced force for inserting the tool into the hollow member. The exterior periphery of each arcuate member includes one or more axial grooves. A plurality of members project from the interior periphery of the hollow member to contact the tool. This provides increased frictional holding of the tool within the hollow member. The projection members surround the interior periphery to provide a corrugated pattern. One of the arcuate portions is thicker than the other. Both arcuate portions have the same thickness at the grooves. One arcuate portion defines an arc of about 200.degree. and the other arcuate portion defines an arc of about 150.degree..
Additional objects and advantages of the invention will become apparent from the detailed description of the preferred embodiment, and the appended claims and accompanying drawings, or may be learned by practice of the invention.